Abstract
The Brn-5 protein plays an important role in the control of cellular development and belongs to a class of transcription factors that usually contain two domains: the POU homeodomain (POU(HD)) and the POU-specific domain (POU(S)). Since high-quality crystals suitable for crystallographic studies of the proteins of this class are difficult to obtain, all the known structural information available is for POU(HD) and/or POU(S). This paper describes several critical steps that allowed the production of high-quality crystals of the full-length Brn-5 protein complexed with its cognate DNA.